1. Reproductive System Nestor T. Hilvano, M.D., M.P.H.
(Images Copyright Discover Biology, 5th ed., Singh-Cundy and Cain, Textbook, 2012.)

2. Learning Objectives
Describe the structures and functions of the male reproductive system (gonads, genital ducts, and glands, and external genitalia).
Trace the passage of sperm cells from the testes to the urethra.
Describe the structures and functions of the female reproductive system (gonads, genital ducts, and external genitalia).
Describe the events and control of the menstrual cycle.
State the site of fertilization and implantation?
Describe ectopic pregnancy.
Define tubal ligation and vasectomy.

3. Reproduction Creation of new individuals from existing ones
Sexual – fusion of 2 gametes to form a zygote (offspring)
Male gametes- sperm cells (spermatozoas)
Female gametes- egg cells (ova/ oocytes)
Meiosis- gametes formation; chromosomes number reduce from diploid into haploid chromosomes (1n)
Sperm cells= 22 +X, or 22 +Y
Egg cells= 22 +X

4. Figure 33.3 Sexual Reproduction Requires the Production of Haploid Gametes through Meiosis
(a) Spermatogenesis produces haploid sperm. (b) Oogenesis produces haploid eggs (ova).

5. Male Reproductive System
Gonads - testes
Genital Ducts
- epididymis
- vas deferens
- ejaculatory ducts
- male urethra
Accessory Glands
- seminal vesicles
- prostrate glands
- cowper’s (bulbourethral)
glands
External Genitalia
- crotum (scrotal sac)
- penis

6. Urinary bladder (excretory system)
Figure 27.4A
Urinary bladder (excretory system)
Seminal vesicle (behind bladder)
Prostate gland
Bulbourethral gland
Urethra
Erectile tissue of penis
Figure 27.4A Front view of male reproductive anatomy
Scrotum
Vas deferens
Epididymis
Testis
Glans of penis 6

7. Rectum (digestive system)
Figure 27.4B
Rectum (digestive system)
Seminal vesicle
Urinary bladder (excretory system)
Vas deferens
Ejaculatory duct
Pubic bone (skeletal system)
Prostate gland
Erectile tissue
Figure 27.4B Side view of male reproductive anatomy (with nonreproductive structures in italic)
Bulbourethral gland
Anus (digestive system)
Urethra (excretory system)
Penis
Vas deferens
Epididymis
Glans of penis
Testis
Testicle
Prepuce
Scrotum 7

8. Testes
Testes - in the scrotum, covered by C.T. and divided into lobules
Semineferous tubules of the testes contain male germ cells and sertoli cells (nurse cells)
Leydig (interstitial) cells- endocrine part, produce testosterone hormone
Spermatogenesis- formation of spermatozoas from spermatogonium.

9. Male Genital Ducts
Epididymis – comma-shaped; w/ coiled tubules; function is maturation and temporary storage of sperm cells
Vas deferens – conveys
sperm cells to the lower tract;
What is surgical ligation of vas deferens? __________.
Ejaculatory duct – union of the duct of seminal vesicle and ampulla of vas deferens; enters the prostatic urethra
Urethra – conveys both semen and urine to the outside

10. Glands of Male Reproductive System
Seminal vesicles – secrete a thick clear fluid; contain fructose and prostaglandins and fibrinogen.
Prostate glands – secrete a milky fluid; with acid phosphatase
Bulbourethral glands – secrete mucus and alkaline fluid; functions are lubrications during sexual contact
Semen – consists of sperm and secretions of these glands (about million of sperm in 5 ml of semen)

11. Penis
Erectile tissue = composed of corpora cavernosa and corpus spongiosum
Prepuce – foreskin
Richly supplied with nerve endings and blood vessels
What erectile tissue does the penile urethra passes through?

12. Female Reproductive System
Figure 27.3C
Female Reproductive System
Oviduct
Ovary
Uterus
Rectum (digestive system)
Urinary bladder (excretory system)
Pubic bone (skeletal system)
Cervix
Urethra (excretory system)
Vagina
Figure 27.3C Side view of female reproductive anatomy (with nonreproductive structures in italic)
Shaft
Prepuce
Clitoris
Glans
Vulva
Labia minora
Labia majora
Anus (digestive system)
Vaginal opening 12

13. Female Reproductive System
Gonads – ovaries; produce
oocytes and hormones
(estrogen & progesterone)
Genital Ducts and Chambers:
- oviducts (fallopian tubes)
- uterus
- cervix
- vagina
External Genitalia
- vulva (labia minora, labia
majora, hymen, clitoris)
- Bartholin’s glands

14. Endometrium (lining of uterus)
Figure 27.3A
Oviduct
Ovaries
Follicles
Corpus luteum
Uterus
Wall of uterus
Endometrium (lining of uterus)
Cervix (“neck” of uterus)
Figure 27.3A Front view of female reproductive anatomy (upper portion)
Vagina 14

15. Female Gonads
Ovaries- each ovary contains many ova (with primary oocyte) and produce hormones
What is oogenesis?
1o oocyte enter meiosis I and stop at birth and resume during puberty at ovulation
Ovulation expels the ovum from the mature (graafian) follicle to the pelvic cavity as 2o oocyte
Meiosis II is completed at fertilization
Corpus luteum secretes hormones, estrogen & progesterone (help to maintain pregnancy)
If the egg is not fertilized, the corpus luteum degenerates

16. Differentiation and onset of meiosis I
Figure 27.5B_1
Before birth
Ovary
Diploid cell
Differentiation and onset of meiosis I
Primary oocyte within follicle
Primary oocyte
Figure 27.5B_1 Oogenesis and the development of an ovarian follicle (part 1)
(arrested in prophase of meiosis I; present at birth) 16

17. Completion of meiosis I and onset of meiosis II
Figure 27.5B_2
Growing follicle
Completion of meiosis I and onset of meiosis II
Mature follicle
Ruptured follicle
First polar body
Figure 27.5B_2 Oogenesis and the development of an ovarian follicle (part 2)
Secondary oocyte
(arrested at metaphase of meiosis II; released from ovary)
Ovulated secondary oocyte 17

18. (arrested at metaphase of meiosis II; released from ovary)
Figure 27.5B_3
Ruptured follicle
First polar body
Secondary oocyte
(arrested at metaphase of meiosis II; released from ovary)
Ovulated secondary oocyte
Entry of sperm triggers completion of meiosis II
Second polar body
Figure 27.5B_3 Oogenesis and the development of an ovarian follicle (part 3)
Corpus luteum
Mature egg (ovum)
Degenerating corpus luteum 18

19. Figure 33.4 Fertilization Occurs When a Single Sperm Enters the Egg
(a) Sperm are many times smaller than eggs, as can be seen in this scanning electron micrograph of a swarm of sperm surrounding a single human egg. (b) The tail of a sperm consists of a whiplike flagellum, which helps it wriggle into the uterus and through the oviduct to meet the egg. The acrosome contains enzymes that help the sperm penetrate the egg’s outer covering. (c) Although many sperm are present on the surface of the egg, only one can penetrate to fertilize the egg.

20. Female Genital Ducts and Chambers
Oviducts (Fallopian tube) –
fertilization occurs at the ampulla of fallopian tube
Uterus – implantation in the
endometrium of uterus (uterine corpus)
* What is known as implantation of embryo outside the uterus?
* What is tubal ligation?
Cervix – lower part of uterus; with cervical glands secreting mucus that lubricate the vaginal canal.
Vagina – birth canal; copulatory organ

21. Female’s External Structures
Vulva consists of
- labia majora
- labia minora
- hymen
- clitoris = counterpart of
penis in males
Bartholin’s glands

22. Menstrual Cycle
Menstruation – 3 to 5 days; pre-ovulatory phase; hormones are low
Proliferative phase (follicular) – endometrium regrows; influence by estrogen from developing ovarian follicles, secrete thick mucus
Ovulation – on day 14; expelled ovum
Secretory phase (luteal) – endometrium thickens, increase vascularization, influence by progesterone (and estrogen) form corpus luteum

23. Figure 29.9 The Human Menstrual Cycle Depends on the Sequential Release of Several Hormones
Follicle-stimulating hormone (FSH) launches a new menstrual cycle by stimulating the growth of ovarian follicles. Developing follicles produce estrogen. When estrogen levels reach a certain threshold, they trigger release of luteinizing hormone (LH) from the pituitary, which triggers ovulation. An estrogen, especially the large amounts of progesterone secreted by the corpus luteum, stimulates a buildup of the uterine lining in preparation for a possible pregnancy. If fertilization fails to occur, the corpus luteum dies after about 14 days, hormone concentrations crash, and the uterine lining is sloughed off.

24. Homework
Define terms: fertilization, implantation, menstruation, ovulation, vasectomy, tubal ligation, ectopic pregnancy.
Give the function or secretion/s of the epididymis, prostate gland, seminal vesicles, bulbourethral gland.
Give the female counterpart (homologue) of the following male structures:
a) penis
b) scrotum
c) testes
4. Explain why male urethra is both a urinary system and a reproductive system?